I think there's some mileage in the concept, especially since the impact of cybertronian intervention and technology has really only been barely touched on in the previous films, while at the same time it was touted as integral to our species' development.

Probably won't happen in TF4, since I get the feeling they won't want to mess with a profitable formula, but if another film is made, with a soft reboot and/or a new director, it could definitely be a way to set itself apart from the previous films.

An interesting idea but I could see reasons why they would never go for it.

Hasbro wouldn't like it because for them the movies are all about how to get a nice uptick in the number of toys they can move. Hasbro doesn't seem to care that the Decepticons are some of the biggest jobbers on film, just that they are there so they can sell the retailers on why they need to stock another wave with Megatron or Starscream.

Paramount likely wouldn't go for it because they already have a franchise where a group of heroes fights a bad guy group of humans. They might feel like it was too much like GI Joe only with the good guy parts being played by robots instead of humans.

Really wouldn't fix the hero worship problem the movies have. Sure right now humans are the most powerful thing in the universe and a member of NEST could kill Decepticons with a sling shot. But as soon as humans were introduced as bad guys even the rail gun from the second movie would be useless against the Autobots.

It also makes Prime look kind of foolish. The whole reason for Prime giving up on his race and his planet was because he's so damn naive about humans not being bungholes. So the films can't show that humans can be worse than the Decepticons.

Almost worth it though for the rage of the people who have the crazy idea that the movies shouldn't have any human in them at all.

I remember talking to some of my friends on X-box live about this. It was on the topic of Rescue Bots, but still, what would Transformers be without Decepticons? It was basically unanimous that Transformers just wouldn't be the same without the Decepticons. It's like saying what's the Rebel Alliance without the Empire?

The Autobots and Decepticons are meant to be together. Without either one, the franchise is just not going to work. But that's not to say I wouldn't welcome the idea of human villains, it's just that Decepticons are a must.